Dyeing wool



Patented Sept. 12, 1933 UNITED STATES PATENT OFFICE *Germany, assignor to I. G. Farbenindustrle Aktiengesellschaft, Frankfort on the Main,

Germany No Drawing. Application January 5,1931, Serial No. 506,757, and in 1930.

5 Claims. The present invention relates to improvements in dyeing wool.

In dyeing woolwith badly levelling dyestuffs i. e. with acid dyestuffs or chromium developer dyestuffs, it has hitherto been usual and necessary to carry out the dyeing process at or near the boiling temperature: of the bath since only in this way could the dyestuff be caused to go on to the wool satisfactorily.

I have now found, contrary to expectation, that Wool and woollen goods can be dyed even at least 20 C. below he boiling temperature of the bath, as for example in a bath heated to from to 70 C. when substances which have a strong levelling action are addedto the dyebaths in addition to larger amounts of easily water-soluble strongly acid agents than are usually employed. The substances having a strong levelling action are non-dyeing sulphonation products of organic compounds containing at least 8 carbon atoms in the molecule i. e. sulphonic acids or sulphuric acid esters of aliphatic, aromatic, aliphatic-aromatic, hydroaromatic. and heterocyclic compounds containing at leasltS carbon atoms as for example stearic, palmitic, ricinoleic or oleic acids, cetyl or dodecyl alcohols or like high molecular alcohols, naphthenes or naphthenic acids, benzyl naphthalene, tetrahydronaphthalene, aryl fatty acids, such asTwitchell fatty acids, cholesterol or quinoline. form of their salts, as for example as the ammonium or sodium salts and the like which are more easily handled than the free sulphonation products but give the same dyeings when employed together with the strongly acid agents. In so far as sulpho-carboxylic acids are chosen, they may be employed in the form of the free acids or of the acid or neutral salts. Those substances which have a high affinity for animal fibres i. e. acid reacting substances are especially active. The water-soluble strongly acid agents to be added besides the sulphuric derivatives maybe chosen from acetic, formic, sulphuric or lactic acids or sodium acid sulphate and the like.

The quantities of the sulphonation products V employed are generally between 0.2 and 30 per cent by weight of the goods to be dyed, the quantity varying with the nature of the goods and-the nature of the dyestuffs employed. The quantity of the strongly acid agents hitherto usual corresponds to, or is, from 1 to 4 kilograms of sulphuric acid of 66 B or from 5 to 12 kilograms of sodium acid sulphate together with from 10 to 20 kilograms of crystalline Glaubers salt or from 3 to 10 kilograms of acetic acid of 6 B They are preferably employed in the Germany January 25,

strength or from 0.5 to 2.5 kilograms of an 80 per cent formic acid if the bath be employed in a quantity of from 30 to 50 times the weight of the goods per each 100 kilograms of the latter. On working in accordance with the present invention the quantity of acid agent or the acidity of the baths is increased by from 20 to 50 per cent.

The process according to the present invention is-particularly suitable for dyestuffs with which it is diflicult to obtain level dyeings under the usual conditions by reason of their possessing too great an affinity for the wool fibres.

.The following examples will further illustrate the nature of this invention but the invention is not restricted to these examples.

Example 1 100 kilograms of woollen piece goods are dyed for of an hour at C. with a combination of 0.15 kilogram of Cyananthrol R (Schultz, Farbstofftabellen, 6th Edition, Vol. 1, No. 859), 0.15 kilogram of Wool fast yellow 3G (ibid, Vol.2, page 118), 0.2 kilogram of Supramine red B (ibid, Vol. 2, page 104) with an addition of 4 kilograms of sulphuric acid and 1 gram of sodium palmitic sulphonate per liter of the dyebath. Very uniform dyeings are obtained and the structure and natural touch of the wool is entirely preserved.

Example 2.

100 kilograms of woollen piece goods are dyed at 60 C. with 2 per cent of Sulphoncyanin GR Extra (ibid, Vol. 1, No. 257) in the presence of 2 grams of cetyl sulphuric ester per liter of the dyebath and 4 per cent of acetic acid. While, under the usual conditions; the said dyestufi' yields completely uneven dyeings, under the conditions specified in this example the goods are dyed uniformly.

Example 3 100 kilograms of woollen piece goods are dyed at 65 C. in the course of of an hour. with from 3 to 4 cubic meters of a'bath of a combination of 0.15 kilogram of Cyananthrol R, 0.9 kilogram of Wool fast yellow 3G, 1.2ki1og'rams of Supramine red B, 4 kilograms of sulphuric acid, and an additionof 1 gram per each liter ofthe bath of benzylnaphthalene sulphonic sodium salt (obtainable by condensation and sulphonation of benzyl halide with naphthalene with the aid of concentrated sulphuric acid). A very good levelling eifect and very uniform dyeings are obtained in contrast to working without the said addition of the sulphonic salt.

Similar good results are pbtained when the said sulphonic salt is replaced Dyan-equal quantity of the so called Twitchellsfat splitter which is a sulphonated condensation product of stearic or like fatty acid with aromatic compounds such as benzene, toluene or naphthalene. The structure of the wool and its original touch are completely maintained after dyeing.

The aforesaid sulphonation products may be replaced by from 2'to 2% times their weight of tetrahydronaphthalene sulphonic acid, the quantities of the dyestuffs being varied if desired to 0.5 kilogram each of Cyananthrol and ofWool fast yellow and 0.6 kilogram of Supramine red.

Example 4 100 kilograms of woollen piece goods are dyed at 65 C. inthe course of of an hour with a bath consisting of 0.15 kilogram. each of the dyestuff obtainable from 4-brom-1-aminoanthraquinone-2-sulphonc acid and acetyl paraphenylnediamine and of Wool fast yellow 3G together with 0.2 kilogram of Supramine red B together with 4 kilograms of sulphuric acid and an addition of 1 gram per each liter of the bath of naphthenic sulphonic acid. Very'uniform dyeings are obtained and the wool retains its structu're and its original. touch after dyeing.

Example 5 100 kilograms of woollen piece goods are dyed 'at 65 C. with l per cent of the dyestufl' obtainlevelling dyestuffs, the step which comprises dyeing with' a hot bath at temperatures between 50 and about 0., said bath containing a non-dyeing sulphonation product of an organic compound, containing at least 8 carbon atoms in its molecule, and a substantial quantity of an easily water-soluble strongly acid agent.

2. In the process of dyeing wool with badly levelling dyestuffs, the step which comprises dyeing with a hot bath at temperatures between 50 and about 80 C., said bath containing a non-' dyeing sulphonation product of an organic compound, containing at least 8 carbon atoms in its molecule, and a substantial quantity of an easily water-soluble strong acid.

3. In the process of dyeing wool with badly levelling dyestuffs, the step which comprises dyeing with a hot bath at temperatures between 50 and about 80 (2., said bath containing from 0.2 to 3.0 per cent by weight of the wool oi. a non-dyeing sulphonation product of an organic compound, containing at least 8 carbon atoms in its molecule and a substantial quantity of an easily water-soluble strongly acid agent.

4. In the process of dyeing wool with badly levelling dyestuffs, the step which comprises dyeing with a hot bath at temperatures between 50 and about 80 C., said bath containing from 0.2 to 3.0 per cent by weight of the wool of a non-dyeing sulphonation product of an aliphatic compound, containing at least 8 carbon atoms in its molecule, and a substantial quantity of an easily water-soluble strongly acid agent.

-5. In the process of dyeing wool with badly levelling dyestuffs, the step which comprises dye- .ing with a hot bath at temperatures between 50 and about 80 C., said bath containing from 0.2 to 3.0 per cent by weight of the wool of a sulphonation product of an aliphatic compound, containing at least 8 carbon atoms in its molecule, and 'a substantial quantity of an easily water-soluble strong acid.

JOSEPH NUESSLEIN. 

